Refrigerating apparatus



E. F. SCHWELLER REFRIGERATING APPARATUS Original Filed July 3, 1931 Jan. 4, 1938.

2 Sheets-Sheet l Jan. 4, 1938. E. F. scHwr-:LLER

REFRIGERATING AFPARATUS 2`Sheets-Sheet 2 Uriginal Filed July 3. 1931 74 75 Fig; 4 72 73 BY v Hyg @5626/60 /62 ATTORNEYS Patented Jan. 4, 1938 UNITED STATES r i REFRIGERATING APPARATUS Edmund`F.` Schweller, Dayton, Ollio,` assignor to General Motors Corporation, Dayton, Ohio, a `corporation of Delaware original imputation July s, 19in, .sensi N."""" 548,583. Patent No. 2,057,746, dated october 20, 1936. Divided and this application June `Z'L 193s, serial No. 87,160

` V12 claims.

This application is a divislonof my co-pending application Serial No. 548,583yflled July 3, 1931.

'Ihis invention relates `to refrigerating apparatus and more particularly to the construction of cabinets, the walls oi" which are heat insulated to prevent the passage of heat therethrough.

` In the manufacture of insulated cabinets, it has been proposed to use air spaces inthe walls thereof to prevent the transfer of heat therethrough. Heretofore such practice has been unsatisfactory ior the reason that radiant heat will pass freely through air, and, in addition, the convection currents set up therein Will transfer large amounts of heat therethrough. To overcome the transfer of radiant heat it has been proposed to provide a. dead air space bounded by a thin bright metal foil `or leaf, `such for instance as bright aluminum foil, for insulating purposes. By the term metal foil" is meantthin leaves of metal either with or without paper backing of such thickness that they can be readily formed to any desired shape. It has been found that these bright metallic surfaces of foil radiate but very little heat, and consequently it is possible to utilize air spaces lined with such bright surfaces in heat insulating cabinets. By reducing the size of the air space the other objectional feature of air space insulation, namely loss of heat by convection currents, is removed in that convection currents ordinarily set up are dei creased to a minimum. i

Attempts to adaptsuch thin bright metallic foil to cabinet construction so as to utilize air spaces in the walls thereof for insulating purposes have met with great difficulty. In the rst place, this foil is extremely thin and consequently cabinets must be so constructed as to prevent rupturing of the foil when such cabinets are subjected to the slam test, a test involving the opening and closing of the cabinet door over prolonged periods of time. In addition,` the foil must be so supported within the cabinet wall as to maintain it substantially taut at all times, while at the same time preventing the transfer of heat through these supporting means. Thirdly. the foil being metallic, has a tendency to rattle or cause what is known as a metallic cry and great care must be taken to prevent or render inaudible such cries or other noises.

It is to such structure that my invention particularly relates, having for one of its objects to provide a cabinet4 construction having foil insulation, that is, a cabinet capable of utilizing a thin bright metallic foil to advantage, while at the same time eliminating most ofits disadvan- 5 tages.

Morewparticularly it is an object oi' theinvention to provide the cabinet construction wherein all metallic cries are adequately deadened, rupturing of the foil is prevented, and a proper spac- 10 ing of the foil is provided.

A further object of the invention is to provide an improved foil construction whereby the layers of foil may be formed by winding a continuous strip of foil continuously around four sides of the l5 cabinet and to` provide various constructions of insulated cabinets adaptable `for easy and economcal` assembling. i

Further objects and advantages ofthe present invention willbe apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the invention is clearly shown.

lIn thedrawings:

Fig. 1 is a vertical transverse section through 25 a refrigerator cabinet embodying one. form of wound foil insulation;

Fig. 2 is a fragmentary sectional view taken on theline 2--2 of Fig. 4;

Fig. 3 is a fragmentary sectional view taken on 30 the line 3--3 of Fig. 4;

Fig. 4 is an enlarged view of an upper corner of Fig. 1; i

Fig. 5 is a sectional view similar to Fig. 4 illustrating a modified construction of wound foil insulation;

Fig. 6 is a view illustrating a method of making the corner piece shown in Fig. 8;

Fig. 'I is a sectional view taken along the line l-l of Fig. 6; and l Fig. 8 is `a. sectional view taken along the line 8-8 of Fig. 1. i

In orderto illustrate one aspect of my invention,\I have disclosed a refrigerator cabinet generally designated as 20. cabinet includes a lower machinery compartment 21 formed within the' framework which includes upright corner members 22 and horizontal cross members 23. The food storage compartment 24 is supported above the machine compartment. This food com- 50 partment is enclosed by a one-piece box-shaped metal porcelain lining secured at its front edges to the door opening of the cabinet.

According to my invention there is provided about the inner liner 1| a continuous strip of foil which is-wound a plurality of times about the inner liner to provide a plurality of layers of foil numbered 12 to 15 inclusive in spaced relation, As better shown in Figs. 2, 3 and 4, the foil is provided with threads 15 and 11 arranged on either side of the continuous strip of bright metal foil.

This form of insulation is preferably constructed by fastening one end of the continuous .strip of foil together with the threads upon the opposite sides of the foil to a portion of the inner -`liner as shown at 15 in Fig. 1. VSpacing members numbered 1.9 to 52 inclusive, having matched V-shaped grooves and corresponding projections on opposite sides, are used to space the layers of the strip of foil winding so as to provide air spaces between the layers. These spacing members are adapted to t along four of the edges ofthe inner liner and also upon each other.

The winding is performed in the following manner: After the continuous strip of foil is attached to the inner liner as at 15,'the innermost spacing members 19are fastened,preferably by glue or cement, to the four diagonal opposite edges about which the winding is to take place and the first turn of foil 12 passes around and rests upon the four spacing members 15 which have been fastened to the inner` liner; after the rst turn is made about the inner liner, the spacing members 55 have their inner groovesl glued or cemented in place on top of the rstturn of foil directly outside of the spacing members 15; after the spacing members 80 are put in place. a second turn of foil 15 is wound about the spacing members so as to provide a second layer of foil; and then similar spacing members 8| are placed at the four corners on top of the second layer` of wound foil 13 directly outside the spacing members 50 and then a third turn ofthe wound foil is taken about the spacing members 8|; after this, similar spacing members 82 are placed on the third turn 14 of the woundk foil directly outside of the spacing members 8| and a fourth turn of foil is taken around the spacing members' 52 and the loose end of foil is fastened either to the outer layer of foil 19 or to one of the spacing members. It will be understood' that the winding can be performed without the use of the threads 15 and 11, if desired, but the threads are preferably employed to prevent the rattling and the metallic cry of the lfoil and also to prevent its rupture during the Winding operation.

After the last turn of foil is completed and fastened to the spacing members, additional spacing members4 5| are provided upon the outside at the four corners of the wound construction directly on top of the outer layer of foil and the other spacing members. vThese spacing members 5| are preferably fastened to the outer layer of the foil similarly to the other spacing members by a suitable adhesive. This completed construction is then preferably slipped into the outer liner 42 which is an open one-piece box-shaped metal member. This outer liner preferably restsupon the horizontal members 25 and is fastened therein.

A porcelain sheet metal covering 5I is provided on top of the cabinet spaced from the outer liner 4| by chip board 35 and the sides of the cabinet are similarly provided with sheet metal covering 36 and 31 also similarly provided with chip board which is inserted between the coated sheet metal covering and the outer liner.

In order to insulate the rear wall of the cabinet, a frame 55 is provided which is wound in such a manner so as to provide air spaces formed by the spaced sheets of bright metallic foil. The frame 55 preferably comprises a rectangular wooden structure or low conducting material. 'Ihe foil is placed upon the rectangular frame 55 in a peculiar manner. 'Ihe continuous strip of foil is fastened to one edge of the rectangular frame 55. In Fig. 8, the foil has one end attached to the lower portion of the frame 55. A The foil is then rst wound aroundthe rectangular frame 55 for one complete turn 50, and then spaced cardboard members 51 are attached to the upper and lower ends of the rectangular frame 55 over the rst turn or layer of foil 65 and a complete turn 5| of foil is woundabout these spacers 51. After this, a wider pair of spacing members 55 are fastened to the upper and lower ends of the rectangular frame over the second turn of winding 5|, as well as over the spacers 51, and a third turn 52 of foil is wound about the pair of spacing members 55. After the third turn 52 of winding, a third pair of wider spacing members 55 are fastened to the upper and lower edges of the rectangular frame 55 over the third turn of winding 52 as well as over the spacer members 55, and a fourth turn of winding 63 is passed around the third pair of spacing members 55. In

this manner, a.' slab of spaced foil insulation is produced by a winding method.

By inspection of Fig. 8 it will be seen that if the windings of foil, either the windings numbered. 12 to 15 inclusive, or the windings of the back panel to 53 inclusive, were extended laterally to the other portion of the outer wall at the rear corners of the cabinet, the air within the innermost space between the inner liner 1| and the first sheet of foil, either 12 or 52, would have access directly to the outer liner. 'I'hus heat might -be transferreddirectly from the outer liner through such a space to the inner liner without passing through all of the spaced sheets of foil and air spaces inbetween. This would reduce the efilciency of the insulation and would tend to cause sweating at that particular point in. the outer wall.

In order to avoid this heat leakage, I have provided an insert ||i| generally in the form of a long rectangular member square-shaped in cross section, having a length sufllcient to extend across the rear wall from one side to the other. Similar members are provided at the side corners of the rear wall and the corner of the rear wall. It will be seen that in Fig. 8 the wound foil designated by the reference characters 12 to 15 inclusive terminates at the rear face of the inner liner 1|, while the slab of wound foil at the rear oi' the cabinet terminates flush lwith the upper wall of the cabinet. By thus shortening the slab of wound foil and decreasing its width, there is provided a space at the corner of the rear wall which extends across the top of the cabinet into which ts the insert Illl and similar spaces are provided for receiving inserts at the sides and bottom of the rear wall.

This insert |0| is a vquarter of a cylinder formed as shown in Figs. 6 and 7. The inserts are preferably formed in the following manner: 'I'he cylinders |55to ||5 inclusive, composed of cardboard having bright metallic foil on one or both sides, are placed in concentric relation and spacing discs are glued onto both ends of the placed between the ends oi tubes III and III;-

a pair of larger concentric rings lll are placed between the ends of the tubes Ill and -Ill and the squared rings Il! are placed on the outside of the tube Ill at suitable points. All oi' these parts are suitably glued or cemented together.

l'.lhe cylinders or tubes may be made entirely ofl a suitable type of bright metallic toil. it desired.

After these cylinders are so assembled, they -are cut into tour parts along the lines il'l and the section line 'i4-1. These assembled quarter cylinders are then used as inserts and one oi.' these inserts lll is placed as shown in Fig. 8.

In Fig. 5, there is shown a moditled form of spacing members `8l which are similar to the spacing members 1! to l2 inclusive shown in the other figures. These spacing members I! also extend across the entire width of one of the edges ci' the inner liner 1i. These spacing members Il consist of cardboard formed into a hollow angle iron shape. These hollow angular spacing members I3 are preferably provided with gummed paper I4 at their inner corner for attaching to the preceding winding of foil so that the. winding operation may be facilitated. By employing spacers of cardboard having a hollow angular shape. the conductivity through the spacing mem' bers is further reduced. In Fig. 5 .no supporting threads I and i1 are shown, but thesemay be used in this modiilcation also if desired.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form. it ls to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

l. An insulating structure including a space to be insulated, insulating means in the form or sheet means extending spirally around said space a plurality of times,'and strip means extending between the layers across the sheet means i'or holding adjacent layers `of the sheet means in spaced relation from each other.

2. An insulating structure including a space to be insulated, insulating means in the form of sheet means extending spirally around said space a plurality of times, and strip means extending between the layers across the sheet means `for supporting said sheet means and for holdingvadjacent layers of the sheet means in spaced relation from each other. 4

3. An insulating structure including a space to be insulated, insulating means in the form of sheet means extending spirally around said space a plurality of times, and strip means extending `between the layers across the sheet means for` holding adjacent layers ofthe sheet meansin spaced relation from each other. the Vstrip means between the dii'i'erent layersbeing located in alignment at a plurality of points about the space to be insulated.

4. An insulating structure including intersecting inner walls enclosing a space to be insulated, insulating means in the form of sheet means extending spiraliy around said intersecting inner walls a plurality of times, 'and strip means extending between the layers across said sheet means for holding adjacent layers of said sheet means in spaced relation, said strip means being located adjacent and being'parallel to intersections of said inner walls.

` 5. An insulating structure including intersecting inner walls enclosing aspace to be insulated, insulating meansin the form oi sheet means extending spirally around said intersecting inner walls a plurality of times, and strip means extending between the layers across said sheet means for holding adjacent layers of said sheet means in spaced relation, said strip means being located in groups extending substantially radially outwardly from adjacent intersections of said walls.

6. An insulating structure including intersecting inner walls enclosing a space to be insulated. insulating means in the form of sheet means extending spirally around said intersecting inner walls a plurality of times, and strip means extending between the layers across said sheet means for holding adjacent layers oir said sheet means in spaced relation, vvsaid strip means being mounted one upon the other at intersections of said walls.

'1.-An insulating structure having inner and outer walls, and insulating means between said walls including a plurality oi.'` superimposed spacing members extending along and supported upon the edges of said inner walls. said spacing members having grooves for receiving the edges of said inner walls. and sheets of bright metallic foil stretched between spacing members at opposite edges, said sheets being held between adjacent spacing members.

8. An insulating structure having inner and outer walls, and insulating means between said walls including a plurality of superimposed spacing members extending along and supported upon the edges of said inner walls. and sheets of bright metallic foil stretched between spacing members at opposite edges, a plurality of threads vstretched upon opposite sides of the foil for pre--` venting ruptures of the foil, said sheets being held between adjacent spacing members, the lnnermost spacing members being' bonded to the inner walls, and the foil being bonded to the spacing members contacting therewith.

9. An insulating structure having inner and outer walls, and insulating means between said walls including a plurality of superimposed spacing members extending along and supported upon the edges of said inner walls. and sheets of bright metallic foil wound about said inner walls iirst over the inner set of spacers and then passing around the inner walls and progressively over successive sets of spacers a plurality 0f times to provide the desired number of layers oi foil.

10. An insulating structure having inner and outer walls, and insulating means between said walls including a plurality of superimposed spacing members extending along and supported upon the edges of said inner walls, and sheets of bright metallic foil wound about said inner walls first over the inner set of spacers and then passing around the inner walls and progressively over successive sets oi spacers a plurality of times to provide the desired number of layers of foil, said spacers being composed oi stil! paper.

11. An insulating structure having inner and outer walls and means for insulating said walls including a plurality of spaced sheets oi bright metallic foil adjacent said walls, some of said sheets terminating at the edges of said inner asl walls, and an insert having a plurality of quarter.

cylinders of sheets of bright metallic foil lling the space between the terminations of some ofsaid sheets.

12. An insulating structure including inner walls enclosing a space to be insulated, insulating means in the form ofvsheet means extending spiraily around said inner walls a plurality of times, and strip means extending between the 

